Depth charge exploder mechanism



Jan. 2, 1962 K. K. DCMINGOS, JR., ETAL DEPTH CHARGE EXPLODER MECHANISM Filed Deo. 24. 1959 United' States Patent 0 3,015,270 DEPTH CHARGE EXPLODER MECHANESM Karl K. Domingos, Jr., George T. Powell, Jr., and John B. Malaspina, Macon, Ga., assignors to the United States of America as represented by the Secretary of the Navy Filed Dec. 24, 19s9,se1-.N0. 862,015 4 Claims. (Cl. 102-7) (Granted under Title 35, U.S. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor. f

This invention relates to a hydrostatic fuze; more particularly it relates to one incorporating a pressure-responsive arming piston.

One object of this invention is to provide a novel hydrostatically armed fuze which is simple and inexpensive, suitable for use in practice depth bombs.

Another object is to provide a -fuze of the character described having a tiring pin and unique safety means to positively prevent ring of the underwater explosive device to which it is attached under unfavorable conditions.

Another object is to provide a new and improved fuze usable over a wide range of hydrostatic pressures ranging from very shallow depths to very deep.

These and other objects of the invention will become better understood by reference to the accompanying drawings in which:

FIG. l is a longitudinal cross sectional view of a depth charge which incorporates the instant fuze;

FIG. 2 is a sectional view taken along line 2-2 of FIG. l; and

FIG. 3 is a sectional view taken along line 3 3 of FIG. 2.

Referring now to the drawings in which like reference numerals indicate like parts throughout the several views, there is shown thereon a depth charge having a symmetrical nose section which has a ilat end, a disk-like symmetrical center section 11, a face of which abuts the at end of the nose. Sections 10 and 11 are joined with cap screws '12 with 0 ring 13 forming a seal therebetween.

The depth charge further has a symmetrical hollow aft section 14, tapering towards the rear, which has a substantially at face abutting the opposite face of center section 11, section 14 being attached to the assembly comprising sections 10 and 11 by aligning bolts 15 which engage threaded holes in member 14 with 0 ring 16 forming a seal therebetween. An explosive charge 17 occupies the hollow except that tapered plug 18 is positioned in the aft portion of the hollow. Fins -19 are attached to section 14 by cap screw 21 which screws into plug 18.

Nose section 10 has a longitudinal, centrally positioned cylindrical well which has an enlarged annular recess at the top, extending from the iiat face towards the nose and further has a plurality of apertures 9 communicating between the bottom of the well and the exterior, the apertures being substantially at right angles to the longitudinal axis of the Well. Nose section 10 is further provided with a pair of parallel cylindrical apertures 8 communicating between the exterior and the well, a longitudinal line in the wall of each aperture meeting longitudinal lines in the wall of the well, which are located 180 apart, at right angles.

Annuler piston 25 is positioned within the well of the nose section and provided with two external and one internal annular grooves, the groove nearest the nose being 3,015,270 Patented Jan. 2, 1962 longitudinally aligned with the said pair of apertures, with pin 26, which is U shaped, being positioned in the apertures so that the end portions protrude into the groove, restraining piston 25 from longitudinal movement. O ring 27 is positioned in the second annular external groove, forming a seal between the piston and the nose section.

Piston 28 is positioned within the aperture of cylinder 25 and is movable within the cylinder with O ring 29 being positioned in the internal annular groove of piston 25 to form a seal between the two pistons.

Abutting both pistons is sleeve cap 31 which encloses an end of sleeve 32 Firing pin spring 33 is positioned within sleeve 32 with one end abutting sleeve cap 31 and the other end enclosed by cap 34 'with washer 35 positioned between the spring and the cap.

Section 11 is provided with a longitudinal centrally positioned cylindrical passageway extending from the face which abuts nose section 10 to a lateral cylindrical passageway, said longitudinal passageway having an enlarged annular recess in the abutting face thereof which has the same diameter as the annular recess in the face of nose section 10. The longitudinal passageway further has a raised shoulder portion just prior to entry into the lateral passageway so as to constrict the entrance.

Disk 36 is centrally perforated and is positioned in the space formed by the annular recesses in the two abutting faces. Sleeve 32 passes through the perforation in disk 36, being guided thereby, and protrudes for a distance into the longitudinal passageway of section y11, where its diameter decreases, forming an internal shoulder, and remains constant thereafter for some distance.

Retaining sleeve 37 having a lianged end is positioned in the bottom of the longitudinal passageway of section 11, the ange abutting the raised shoulder portion thereof, and the other end being enclosed by the smaller diameter section of sleeve 32, the larger diameter section of which is in turn encased in sleeve 38 which lines the walls of the passageway, one end abutting the ange of member 37 and the other end abutting disk 36.

Retaining sleeve 37 has a plurality of apertures, all in the same plane, and normal to the longitudinal axis thereof and firing pin 40, having an annular groove, is positioned so that the apertures are aligned laterally with the apertures in member 37; ball bearings 41 are positioned mostly in the apertures of member 37 but partly in the annular groove of the tiring pin and are constrained from outward movement by the smaller diameter portion of sleeve 32, thus securing the pin from forward movement. The rear end of the firing pin 441 abuts cap 34 while in the secured position.

The lateral passageway of section 11 is provided with a coil spring 45 which is positioned in the bottom thereof. Piston 46, having a central raised portion, is positioned in the cylinder on top of the spring, the raised portion fitting within the coils thereof, and is constrained from rotation by pin 47 which tits partly in a hole in said piston and partly in a lateral slot in member 11; the ends of the slot forming stops for the pin, thus constraining the piston from outward movement when spring 45 is essentially uncompressed and from further inward movement, once the explosive charge 48 is aligned with the tiring pin.

The piston further has a hole, its axis in alignment with the axis of the firing pin 40 when spring 45 is in an essentially uncompressedv condition.

Piston 46 has a substantially centrally positioned `aperture vwhich is filled with primary explosive 48 and an annular groove within which O ring 49 ts and forms a seal.

The lateral passageway of member 11 and the adjoin- 3 ing portion of member 14 have an enlarged annular recess at the top. Piston 46 has an aperture which is above the level of the recess and pin 51, fitting in the aperture and abutting the recessed face, constrains the piston from inward movement.

Member 1.1 further has an aperture communicating between the lateral passageway and the other face thereof which is in alignment with the firing pin and which is filled with a primary explosive charge `52.

Member 14 is provided with an aperture connecting the face abutting member 1v1 and the hollow portion which contains explosive 17, said aperture having an annular recess into which ring 53 is positioned, said aperture being filled with booster explosive 54 with disks 55 positioned in the aperture between the booster and the main charge 17.

In operation, pin 51 is removed and pin 26 may or may not be removed, as the case may be. If a shallow setting is desired, then pin 26 is removed so that the hydrostatic pressure will operate on both pistons 25 and 28. if a deep setting is desired, then only the operation of piston 28 is necessary and pin 26 may be left in place.

The depth charge is now launched into the water where it begins to sink. Water enters the apertures in nose section and the hydrostatic pressure begins to push pistons 25 and 28 or only piston 28, as the case may be, backwards; at the same time, hydrostatic pressure begins to push piston '46 inwardly.

Pistons 25 and 28 or only piston 28, as the case may be, push against sleeve 32, sliding it backwards, and at the same time compressing firing pin spring 33. When sleeve 32 has moved suiiiciently, the smaller diameter section thereof` will be completely to the rear of balls 41 and the larger diameter section will be directly over them. With nothing to constrain them, the balls will be cammed outwardly by the firing pin 40 which is urged rearwardly by its spring 33.

Simultaneously with the rearward movement of pistons 25 and 28, or only piston 28, as the case may be, to cause release of the firing pin, piston 46 moves inwardly in response to hydrostatic pressure, compressing spring 45. When pistons 25 and 28 have moved far enough to cause the firing pin to release, piston 46 will have traveled inward to the point where the primary explosive charge 48 is aligned with the firing pin and is also aligned with primary explosive charge 52. Upon impact, the firing pin sets off charge 48 which sets off charge 52, which in turn sets off the booster charge 54, causing the main charge 17 to detonate.

It will be noted that while the arming piston, 46, is in its outermost position, for example locked in place by pin 51, a cavity therein is longitudinally aligned with the firing pin; if the firing pin is released at this point, it will go into the cavity with insufiicient force to set off primary explosive 48. It will further be noted that even though the cavity in piston 46 is not aligned with the firing pin, no explosion can occur until at least a portion of primary explosive charge is in a position to be struck by the firing pin.

The hydrostatic pressure acting on both the longitudinally and the laterally moving pistons is substantially the same, and the initial tension and gradients of springs 33 and 45 must be chosen so that explosive charge 48 is properly aligned when the firing pin is released.

The force acting to compress the firing pin spring 33 is a function of the hydrostatic pressure acting on the pistons 25 and 28 and the cross-sectional area of the pistons. Thus the force may be controlled by providing a multiplicity of additional concentric pistons, each with its locking pin, so that less than all pistons are free to move.

Fuzes of the instant type are relatively simple and inexpensive to manufacture. They are manufactured from conventional, readily obtainable, and inexpensive materials and the machining is not complex.

Prior to being placed in water, depth charges employ-- ing the instant fuzes are quite safe, as there is no force urging the firing pin towards the detonating charge 48 and further, pin 5]. must be removed before the device will function. Once in water, the fuze will only function when pin 51 has been removed and the depth charge has fallen to a predetermined depth.

The use of the concentric pistons to urge the firing pin allows fiexibility in setting the depth at which the depth charge explodes immediately prior to launching, while the choice of springs and the gradients thereof allows a wide range in establishing said depth.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. In a depth charge, an exploder mechanism which comprises; a first section having a first bore therein, one end of said first bore having communication with the exterior of a depth charge; a pair of concentric pistons positioned in said first bore such that Water entering the end of the first bore has communication with the exterior of the section and will exert pressure thereon when the exploder mechanism is submerged; locking means detachably secured to said section for restraining the outermost of said pistons from movement within the first bore until the locking means is removed therefrom; a second section having a cylinder therein smaller in diameter than the first bore, said first bore and the cylinder being positioned with respect to each other such that one end of the said cylinder communicates with the end of the said first bore opposite to the end thereof having communication with the exterior of the first named section, said first bore and the cylinder having a common axis; a first spring positioned substantially within the first bore and having an end portion extending into the cylinder, one end of said spring being adjacent to the faces of the concentric pistons opposite to the faces to be subjected to water pressure; a firing pin having a blunt end and positioned within the cylinder, the opposite end of said first spring being adjacent to the blunt end of the firing pin in a manner to urge the firing pin toward a fired position when the spring is compressed; means to hold the firing pin in a cocked position until at least one of said pistons has moved a predetermined distance to a firing position; a second bore formed in said second section, said second bore being substantially normal to said cylinder and communicating therewith, one end of said second bore having communication with the exterior of the second section; an elongated piston positioned in said second bore and having a lateral aperture filled with a first primary explosive charge; said elongated piston being positioned within the second bore such that the lateral aperture will be in a position to be struck by the firing pin after the elongated piston has moved to an armed position Within the second bore; restraining means detachably secured to the elongated piston for preventing inward movement of the elongated piston until the restraining means is removed; a second spring positioned between the elongated piston and the bottom of the second bore in a manner to yieldably bias the elongated piston to a safe position and being of such strength that the explosive charge in the aperture of the elongated piston will be longitudinally aligned with the firing pin when the restraining means is detached and the pressure of the water against the elongated piston has reached a predetermined value suiiicient to move the elongated piston to the armed position; means for stopping the elongated piston in said armed position, said last-named means holding the elongated piston against rotation; a second primary explosive charge aligned with said firing pin and with the rst primary explosive charge when the elongated piston has moved to the armed position; and a booster explosive charge abutting the said second primary charge and in communication therewith.

2. The device of claim 1 in which the firing pin holding means comprises a sleeve which surrounds a firing pin having an annular groove, the sleeve having a p'urality of lateral apertures in the same plane and in alignment with the groove in the firing pin, balls positioned within the apertures and projecting into the groove, and a movable sleeve closely surrounding the iirst named sleeve to constrain the balls from outward movement, one end of the movable sleeve abutting the concentric pistons so as to be urged towards the tiring pin thereby, the movable sleeve further having an increased diameter at a point near the blunt end of the ring pin so that it no longer constrains the balls after it has been pushed sufficiently by at least one of the concentric pistons.

3. The device of claim 2 containing the further limitation that the elongated piston has a cavity facing the firing pin and in alignment therewith when the elongated piston is positioned by said holding means which comprises a pin positioned in a lateral aperture near the top of the piston, the ends of the pin protruding from the aperture and being constrained from inward movement by a recessed portion in the outer surface of the depth charge. 4. The device of claim 3 having the further limitation that the stopping means comprises a pin positioned in a hole in the elongated piston, its end protruding and substantially perpendicular to the axis of the elongated piston, and a portion having a longitudinal slot which communicates with the second bore and into which the pin juts, the walls of the slot determining the limits of the movement of the pin and the elongated piston.

References Cited in the file of this patent UNITED STATES PATENTS 1,368,569 Minkler Feb. 15, 1921 1,617,674 Dieter Feb. l5, 1927 20 2,568,712 Bowersett et al Sept. 25, 1951 

